<![CDATA[This research is motivated by language phenomena that frequently occur in academic environments, particularly among students of the Indonesian Language and Literature Education Program (PBSI) at Universitas Muhammadiyah Sukabumi. The phenomena of code-switching and code-mixing in students' daily communication became the focus of this study, as they are considered interesting to examine in order to provide a clear representation of actual language use on campus.This study aims to identify the forms of code-switching and code-mixing, as well as to reveal the underlying factors that cause them. A qualitative descriptive approach was employed, with the observation method used as the data collection technique. Data were gathered through recording students' utterances in their daily communication. The results show 13 data findings, consisting of 3 code-switching data and 10 code-mixing data. Code-mixing data are divided into three types: inner code mixing, outer code mixing, and hybrid code mixing. The factors underlying both phenomena include the speaker factor, the interlocutor factor, habit or informality, the unavailability of appropriate expressions or terms, and the speaker's desire to demonstrate their education or knowledge. These findings indicate that code-switching and code-mixing in PBSI students' communication are not merely variations in language use, but also reflect the speakers' ability to adapt their language choices to the context and communicative needs. Thus, this study contributes to a deeper understanding of language practices among PBSI students in academic settings, particularly that language variation functions as a strategy to build rapport, convey meaning, and adapt to different communicative situations.]]>
